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wkearney99 02-27-2012 04:55 PM

reconnect O2 wires?
I hope there's a special place in Hell reserved for the engineer/bean counter that designed the harness for the forward exhaust O2 sensors. The damn things are not long enough to let me get in there to reconnect the new ones! The driver side is BAD, but the passenger side is WORSE! I cannot, for the life of me, figure out how to get a firm enough grasp of the harness-side connector to get the plug end to secure into it! That and there's just NO room to get hands in there. Again, passenger side is worse.

So if you're planning on doing this job be SURE to allow for a lot of extra time wrestling with damn connectors.

Any tips on dealing with these? I realize they've got the little spring tab in there, getting them loose was a hassle, but they're off now. I'm just unable to get them clicked back together because there's no way to hold the other side!

jeepgcoman 02-27-2012 10:28 PM

Re: reconnect O2 wires?
Sounds like you have the old ones out??? Plug the new ones in BEFORE you screw them in. After plug-in, counterwind the wiring and then screw them in. Fortunately, with my custom headers, mine are all cake to get to without any hassle. It also may be easier to loosen or remove the bolts for the head pipes at the exhaust manifolds. Good luck and let us know what you end up doing.

wkearney99 02-28-2012 08:02 AM

Re: reconnect O2 wires?
Yes, I got the old ones out. You have to press on the tab of the sensor-side of the connector and smoothly pull them apart. The hassle is getting them re-connected and clicked back together. There's really not enough room for my hands to get up in there. The driver side has almost enough, the passenger side doesn't. And it doesn't appear I can get to them from the top either, as that part of the harness is back in the tunnel under the firewall. It's a seriously lame design.

I would greatly prefer not to have to drop the exhaust manifold connection. I can just see those being seized, or worse, to shear off.

I might be able to get a long needlenose pliers up there to hold it.

wkearney99 02-28-2012 04:20 PM

Re: reconnect O2 wires?
I got the passenger side reconnected using a long set of needlenose hose pliers. I used them to reach up behind the harness side connector to pull it down tightly enough to let me shove the sensor connector into it. Had to use a 3/8" socket extension to push it. The pliers look like these:

Oh joy. The driver side harness connector is fooked. Damn tab broke off. Now, that alone wouldn't be a horrible problem as I could just use some zip ties to hold the connectors together (one around each wire end and then a loop between them). No, that would be too easy. On close examination it appears one of the pins has gone missing. Either due to it being a crap connector or my fumbling with it. Either way I'm now officially screwed on it.

I've no idea how the hell I'm going to get up there to deal with it. There appear to be at least four other sensors along the transmission that plug into that harness. I'd have to get all of those loose and then try and thread the whole mess up to the engine compartment. Not sure if that's possible.

Either that or drill an access hole through from the passenger compartment, on the transmission tunnel. If I drill out a hole what sort of plugs can I get that'll keep a decent seal in there again? And how much hassle would it be to get to the metal behind that carpet? Is that going to be worse than wrestling with the harness? I'm guessing the rug is one whole piece, right? Is there enough space either at the tunnel or over from the door to get in there? Probably not, eh?


jeepgcoman 02-28-2012 06:50 PM

Re: reconnect O2 wires?
I don't think I'd drill a hole in the floor. It can be done though and then patch (cover) it with a piece of sheet metal sealed with something like RV metal joint tape....looks like sticky clay. Screw it down on 4 corners. I think I'd take my chances with unbolting the exhaust first. If you're worried about stuck bolts/nuts, soak first with WD40 or some other type penetrating oil like PB Penetrating Catalyst. Please keep us posted.

wkearney99 02-28-2012 08:01 PM

Re: reconnect O2 wires?
The problem won't be solved by dropping the exhaust as that won't really give me any more room to deal with replacing that connector.

But the thought just occurred to me, I could probably just replace the whole length of wire down from where ever it comes from up above in the engine compartment. The trick will be in finding the wires, but if they're up where I can work on them then it'll be a lot less hassle. Then I could just snake the replacement back down to the sensor.

Now the trick will be in finding that four wire connector. Anyone know where to get the connector on the harness side of the wiring? I'd hate to have to buy a whole segment of harness for that side of the engine just to have to cut it apart.

jeepgcoman 02-28-2012 09:10 PM

Re: reconnect O2 wires?
I am not sure you can buy "a whole segment of harness", probably just the whole harness. I am pretty sure you can get plugs though (check with the dealer), and maybe just splice/extend the you say, after you find them. Which tab broke off the plug? Was it the red "lock" tab, or the black "release" tab that you have to depress to remove it?

wkearney99 02-29-2012 05:46 AM

Re: reconnect O2 wires?
These are just black, no red. The release tab on the sensor end slips under a small black 'lip', for lack of a better term, that's in the harness-side connector. That lip broke off. But that's the least of my worries, as the connector inside appears to have lost one of it's pins. So I'll have to splice in a new connector. Which will be practically impossible given the close quarters where the connector is located. It looks like my only option will be to splice a new connection further up the harness in the engine compartment and run new wire down to the sensor connection. The trick will be in finding just that connector.

jeepgcoman 02-29-2012 07:21 PM

Re: reconnect O2 wires?
Try the dealer first, and then if that doesn't work, Cleveland Pick-A-Part. Also, don't know if this site may help or not:

jeepgcoman 03-10-2012 08:07 PM

Re: reconnect O2 wires?
Wkearney99, did you ever get your problem resolved?

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